A night road or a road tunnel middle section is usually illuminated by an artificial light source which hardly influenced by natural light. As a result, in the course of driving at night or in the tunnel middle section, a driver will feel more visual and psychological loads relative to external environment. In order to improve the visual environment of the night road and the tunnel middle section, it is required that the light environment generated by the artificial light source can meet demands for the visual information collection and driving safety, stability and comfort of the driver when the driver drives the vehicle at a certain running speed on the night roads and in the tunnel middle section. Currently, how to determine the parameters, such as color temperature, color rendering and brightness parameter values of the artificial light source, with influence on the light environment to provide guidance standards for light environment setting to achieve a visual recognition level for safe and comfortable road driving has become a problem which has not been well solved.
At home and abroad, the evaluation of light environmental parameters of the night road and the tunnel middle section is mostly conducted according to subjective feelings of drivers or experts to qualitatively evaluate the brightness of the artificial light source or to evaluate the safety and comfort of the night road or tunnel middle section based on the driver's physical and psychological indexes, being lack of the study on driver's visual efficacy under different light source characteristics. Since the driver will have different visual perceptions in different light color environments with differences in needs of identification on objects, color temperature, color rendering, brightness level and other parameters of the light environments must be comprehensively expressed and analysed to comprehensively and objectively reflect the influence of the different light color environments on the driver's visibility. Thus, it is desirable to seek a determining method and system, which can comprehensively, objectively and simply reflect the influence of the different light color environments on the driver's visibility, which can analyse the driver's visibility under different light source characteristics, to obtain light environment parameters under the different light conditions so as to meet the driver's demand for visual recognition.